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That’s interesting. What chemical process is that?

They are doing a bad job in explaining how the pH changes when adding carbonates to water. Either sodium bicarbonate or another carbonate. I tried to understand it by myself and google searches but still haven't found a way. This is the problem: So the water has a pH of 6.35. Which is the pKa value of H2CO3/HCO3-. So in solution at this pH there should be 50% H2CO3, 50% HCO3- and 0% CO32-. So in general they now start calculating stuff with the electroneutrality equation which is: H+= HCO3- + 2*CO32- + OH- . Lets assume that the total of carbonates species is 0.03 mol/L at a pH of 6.35. Than 50%*0,03 = 0.015 mol/L of H2CO3 and 0.015 mol/L of HCO3- in solution. There is also kw/10-6.35=10-7.65 mol/L OH- present in solution. So filling this in the electroneutrality equation: H+= 0.015 + 10-7.65 = 0.015 mol/L. So this is a bit confusing. Since pH is 6,35 it should be H+= 10-6.35 mol/L. Not 0.015 mol/L. My question is. What am I missing here. Can somebody help clear the confusion.

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Not only the dose; many other factors are involved. My brother eats better than I do, works out with weights like a madman, and walks two hours per day.; I eat most anything I want, use sugar, and really need to get back to the gym as I'm gaining weight. He is one year older than me, but he has diabetes ( under excellent control ), and I don't. I gave an example of risk analysis to Dimreepr and MSC in the thread regarding the use of atomic weapons on Japan, in WW2. The probability of an incident, and the severity of the incident, must both be considered; some, in this thread are only considering one or the other. I work in a Chemical plant which, on a regular basis, has up to 70 000 lbs of 95 - 99.99996 % Phosphine, liquified at 700 psi. You can look up the MSDS for yourself as to its dangers. Yet, I worry more about the 15 min drive to work, and back home.

100^9/10^10=100000000->log100100000000=4 Yeah I'm betting this method wouldn't work for 10 digits since it links to 4 which didn't work. Maybe 12 digits? 144^11/12^12=61917364224->log14461917364224=5 Nope! 14? 196^13/14^14=56693912375296->log19656693912375296=6 ✓! So 2, 3, 6, 8, & 14 all check out for this method of placing one repeating digit into a combinatorics problem which I'm betting is where the power rule came from.

Depends on the species. Franklin's 50/500 rule is often cited for humans (I just wrote on this on another thread but can't find atm) and that top number is seen as what is needed for longterm viability and sufficient genetic diversity. Lower numbers and a species can wither. Too much inbreeding, losses of useful genetic variants to genetic drift, etc. Most mutations are deleterious, about 75-80% of single nucleotide variants, so the lucky dice roll of a positive mutation (roughly 1-2%) that adds useful diversity is going to be rare in too small of a population. I've seen debate on the number, but there seems to be some agreement that 500-600 is enough for humans. I know NASA has funded some studies on this, with a longterm view to understanding what are viable populations for establishing colonies on other worlds.

Obviously if anyone 5 digits they would have seen why it is an incompatible way to proof the power rule. 6's log links to 2. Let's try it for next lower even number, 2 digits. 11 {2}, has a value of 1 configurations, x2 is 2. ((2x2)^(2-1))/2^2 = 1. If I did 8 digits (64^7/8^8=262144), I'm betting that since log64(262144)=3 you wouldn't have to do it with 8 again either, because 8's log links to 3. If you had 3 digits 113 131 311 = 3 and (9^2)/(3^3)=3 Let me see if I didn't do 4 wrong: 1123 {4} 1. 1123 2. 1132 3. 1231 4. 1321 5. 2311 6. 3211 7. 3112 8. 2113 9. 1213 10. 1312 11. 3121 12. 2131 1124 {3} 13. 1124 etc... 12 x 2 = 24 so yeah it wouldn't work like I said with 1 repeating it had 4 extra configurations in it. And even if I hadn't multiplied by 2, 16^3/4^4=16, so 4^4 x 12 wouldn't do it. It seems that Newton could have come up with the power rule by using one repeating digit in a combinatorics equation where the logarithms link, like 3 and 8, or 2 and 6.

Dear all, for a biological experiment I have acquired 10 mg of CHIR 99021 (laduviglusib). In order to obtain a 10 mM stock solution I had to dissolve the powder in 2.15 mL of Dimethyl sulfoxide (DMSO). Unfortunately, I tried to dissolve the powder in distilled water. That powder is said to be insoluble in water. In order to obtain again the powder I tried to centrifuge the solution (1500 rpm, 20 minutes), hoping that the powder would precipitate, but nothing happened. I would like to know how to dissolve that solution: I sm thinking to put another 2.15 mL of DMSO in the water solution in order to have a stock solution of 5 mM (which would be fine for me). What would you suggest? Thank you very much.

I'm inclined to think that "dangerous chemical" means dangerous to those who work with the chemical as a chemical as well as to those in the vicinity of any accident from working with the chemical. Dangerous chemicals require more stringent safety protocols, which reduce the likelihood of deaths but not the danger. The danger from sugar does not come from it being a chemical, but rather from it being a food. Similarly, the danger from drowning in water does not come from water being a chemical. On the other hand, safety protocols demand that no one travel in an elevator with liquid nitrogen. That is, liquid nitrogen might not be especially dangerous, but it does have its hazards which can lead to death. Ethers are not especially dangerous... unless they're old, in which case, distilling them can lead to an explosion. Also, dangerous chemicals need not be just about death, but also serious injury. For example, osmium tetroxide is dangerous because it can lead to blindness if any gets on the eyeball.

I agree. But the dose is really important.

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Obviously the OP was wrong about calculating the configurations but, given 10 x ((25 x 10!)/4!), 1123456789 {0} is like 1/100th of the possible combinations of repeating number so in theory there's plenty of room left for the rest of repeating configurations. And this is why the derivative of an exponent maximizes its dimensions.

How about posting stuff that has context and explanation, that’s on-topic? That might help. I mean, what does “It's the people who pay for protection, that inspires a war...” mean? Who are the people to which you refer? How are they paying for protection? How does this “inspire war”? How is any of this relevant?

What information would convince you?

I still think HFCS is more likely to harm you. In the US between 1975 and 2009 109 people died from botulism. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5460764/#:~:text=Overall mortality was 3.0% with,other%2Funknown botulism cases]. HFCS is linked to diabetes, and while I don't know to what extent, in 2021 almost 400,000 people in the US died as a result of diabetes. https://www.healthline.com/nutrition/why-high-fructose-corn-syrup-is-bad#4.-Excessive-intake-is-linked-to-diabetes

A femtogram of BTX is less likely to harm you than a tonne of HFCS. Ask Paracelsus. We are, in fact, exposed to both. (there are going to be traces of BTX in some of the things you eat). And there's plenty of HFCS. Which one is more likely to harm you?

When I was in Paris ,aged 15 my host family took me out for the day to look at the Arc de Triomphe. As we looked at Napoleon's different victorious battles and dates that were inscribed on the monument I asked out loud and in complete naiveté "Where is Waterloo?" To complete silence . I was completely unembarassed .I think I was put right when we got home. Later I amused my friends by describing bad things as "terrible" when that actually means "really good"( a mistake categorised as a "false friend") Ps "espèce de con " or "espèce de conard" is a fine insult and "Le Canard enchainé" was the main satirical weekly magazine back then.

Can a 10 km wide asteroid be a "rubble pile"? However, composition shouldn't make any difference. A series of nuclear explosions in the path of ANY 10 km wide asteroid will do two things: it would fuse together any loose rocks facing the explosion, and cause outgassing with each explosion. ENOUGH of these explosions, at the correct distance, can change its' course enough to miss earth. Why not? Remember, it won't get here for 100 years.

@CharonY Anything to say here?

When in France, I greatly amused some locals by referring to the cruise liner company as Conard, instead of Cunard. This was how I learned that connard is French for asshole. I wasn't too embarassed, thanks to the friendly company and my already earned status as something of a clown.

As far as the face-on-face contact problem goes, I realize that I can't remove contact points willy-nilly. But it is important to make sure, each contact normal is facing the same direction. Sometimes they don't due to numerical issues. So, I remove contacts that don't face the same direction, as the normal returned by the GJKEPA. Sometimes objects will interpenetrate a tiny amount, and pop out on another side, resulting in a bad GJKEPA normal. This is particularly the case for very neat stacks. Messy stacks don't have this problem. But it seems as long as I used small enough time steps, this doesn't happen. Is this the correct way to do it? My next question: What is the best way to find contact data? When GJKEPA returns a normal end location, that is all I need to feed into my contact force solver, when one of the objects is a sphere. For polytopes this is not the case. I am currently going through all vertex face and edge combinations if a collision was detected. This seems inefficient. Also, I want the geometry of the objects to be consistent between collision and contact forces. But because I am using margins with collision detection, all the edges and vertices are beveled. Is it sufficient for the signed distance of the unenlarged objects to be negative or less than the sum of the margins? Thank you. I did not have a computer for a few weeks.

You’re still going to have mutations.

I mean the power rule has to be a derivative of the combinatorics above, where there is only one repeating number that repeats once, in that combinatorics you have to leave one number out to find the number of combinations and then swap it for one other number. For 4 digits you could have 4 repeating once, twice, thrice, or all numbers could be 4, same for 3,2,1; where altogether including the 4 x 24 value, you have a total of 4^4 possible figurations. But when only one of those repeats once, it's only 16 possible configurations. The derivative 16^3=16 x 4^4. You can clearly see that the formula where the power rule comes into play is logn(x), where x=c times d, where if the total number of possible configurations is d=a^b and n=a times b. Finally, c=total number of possible configurations with one repeating number that repeats once as shown above. From that you can recognize the power rule a^b = (a times b)^(b-1), and its integral a^b=(a/(b+1))^(b+1) which has nothing to do with the economic optimization problem I had written out about the garden other than it using a the power rule one time. So if you had up all those functions in the OP picture you should get 10^18/10^10=10^8, log100(10^18)=9; (10^10)'=100^9

Let's say we have a small, genetically limited population due to bottleneck/founder effect - is there a way for such a population to increase it's genetic diversity other than by introducing new DNA from the outside? I am talking about small, genetically limited populations like the Amish.

I completely relate to this! Your upper lip probably curled when you purposely misspelled it above. We're proud of our use of the written word, and go to some effort to craft reasoned responses hoping they're clearly understood. Having a word flagged in an otherwise well-crafted sentence and hitting submit is like having a great conversation with someone but belching every time you try to say their name. Ignore those flags at your peril! As a side note, watch out for the double consonants and vowels. I've noticed a tendency of mine to triple tap when gooogling flaggged missspelllings due to embarrrasssment at my fooolishnesss.